value: 1 Use the same encryption configuration as the database. This is the
default option when
encryption_config is empty.
For example, if the database is using Customer_Managed_Encryption, the
backup will be using the same Cloud KMS key as the database.
GOOGLE_DEFAULT_ENCRYPTION
value: 2 Use Google default encryption.
CUSTOMER_MANAGED_ENCRYPTION
value: 3 Use customer managed encryption. If specified, kms_key_name
must contain a valid Cloud KMS key.